Abstract: In order to address the issues of poor flame retardancy,insufficient mechanical strength,and high cost associated
with polyurethane materials used in mine grouting,this study introduces organically modified sepiolite (SK-SEP) to achieve
synergistic regulation of the material′s curing characteristics and mechanical properties. The sepiolite underwent synergistic
modification using silane coupling agent (KH550) and stearic acid (SA). Significant enhancements in hydrophobicity and interfacial
compatibility were confirmed via FTIR,XRD,SEM,and contact angle testing. The influence of SK-SEP dosage on the
composite material′s curing behaviour,rheological characteristics,and mechanical properties was systematically investigated.
Results indicated that SK-SEP addition significantly reduces peak curing exothermic temperature,prolongs curing time,and increases
slurry viscosity. The compressive strength of the composite material initially increased then decreased with rising SKSEP
content,achieving optimal performance at a mass fraction of 4%. At this point,the maximum curing temperature was 99
℃,the curing time was 145 s,and the compressive strength reached 82. 41 MPa,representing a significant improvement over
pure polyurethane. This research provides an effective methodology and practical basis for developing high-performance,highsafety
polyurethane grouting materials.

Key words: 有机改性海泡石　聚氨酯注浆材料　固化温度　流变性能　抗压强度